Lösung.

Es wird

$ \mbox{$\displaystyle \begin{array}{rcl} \displaystyle\int_\gamma\dfrac{1}{z}\... ...ystyle\int_0^{2\pi} \text{i}n\;\text{d}t \;=\; 2\pi\,\text{i}n\;. \end{array}$}$